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This correspondence presents a construction of quasicyclic (QC) low‐density parity‐check (LDPC) codes based on a special type of combinatorial designs known as block disjoint difference families (BDDFs). The proposed construction of QC‐LDPC codes gives parity‐check matrices with column weight three and Tanner graphs having a girth lower‐bounded by 6. The proposed QC‐LDPC codes provide an excellent performance with iterative decoding over an additive white Gaussian‐noise (AWGN) channel. Performance analysis shows that the proposed short and moderate length QC‐LDPC codes perform as well as their competitors in the lower signal‐to‐noise ratio (SNR) region but outperform in the higher SNR region. Also, the codes constructed are quasicyclic in nature, so the encoding can be done with simple shift‐register circuits with linear complexity.